The disclosed invention relates generally to concrete mixtures.
Due to its strength, durability, and relatively low cost, concrete remains probably the most important building material used today.
Concrete is simply a mixture of fine and coarse aggregate which is bound together by a cementing agent. The coarse aggregate is often gravel and the fine aggregate is often sand. The cementing agent can be any one of a number of commonly used cements, such as Portland cement, hydraulic limes, natural cement, masonry cement, Pozzolan cement and slag cement, probably the most common being Portland cement.
A chemical analysis of Portland cement as shown in the following Table 1, indicates that the composition of Portland cement varies depending upon the type of rock which is used to manufacture it and in which part of the country this rock is mined.
TABLE 1 __________________________________________________________________________ ANALYSIS OF PORTLAND CEMENTS.sup.a WHERE MADE MADE FROM SiO.sub.2 Fe.sub.2 O.sub.3 Al.sub.2 O.sub.3 CaO MgO SO.sub.3 Loss __________________________________________________________________________ New Jersey Cement rock and 21.82 2.51 8.03 62.19 2.71 1.02 1.05 Pennsylvania limestone 21.94 2.37 6.87 60.25 2.78 1.38 3.55 Michigan Marl and clay 22.71 3.54 6.71 62.18 1.12 1.21 1.58 Ohio 21.86 2.45 5.91 63.09 1.16 1.59 2.98 Virginia 21.31 2.81 6.54 63.01 2.71 1.42 2.01 Missouri Limestone and clay 23.12 2.49 6.18 63.47 0.88 1.34 1.81 Pennsylvania.sup.b 23.56 0.30 5.68 64.12 1.54 1.50 2.92 Illinois 22.41 2.51 8.12 62.01 1.68 1.40 1.02 Germany Blast furnace slag 20.48 3.88 7.28 64.03 1.76 2.46 Belgium limestone 23.87 2.27 6.91 64.49 1.04 0.88 France 22.30 3.50 8.50 62.80 0.45 0.70 England 19.75 5.01 7.48 61.39 1.28 0.96 Germany.sup.c Iron ore and limestone 20.5 11.0 1.5 63.5 1.5 1.0 __________________________________________________________________________ .sup.a From Meade's "Portland .sup.b White Portland cement. .sup.c Seawater cement.
The key ingredients of the Portland cement are calcium oxide (lime), silicon dioxide and aluminium oxide (alumina). With reference to the chemical analysis of Portland cement in Table 1, one can see that with respect to the key ingredients, the relative portion of silicon dioxide to aluminum oxide is approximately 3:1 and the proportion of calcium oxide to the sum of the silicon oxide and aluminum oxide is approximately 2:1.
When water is mixed with the Portland cement, the product sets in a few hours and hardens over a period of weeks. The initial setting is caused by the interaction of water and tri-calcium aluminate, 3CaO.Al.sub.2 O3. The subsequent hardening and development of cohesive strength are due to the interaction of water and tri-calcium silicate, which is 3CaO.SiO.sub.2. These compounds are in the form of gelantinous hydrated products which surround and cement together the individual coarse and fine aggregates. There is also some vary slow setting due to the hydration of di-calcium silicate, 2CaO.SiO.sub.2, however, the ultimate cementing agent is probably gelantinous hydrated silica, SiO.sub.2..sup.2
Another type of commonly used cement besides Portland cement is slag cement, which is a mixture of granulated blast furnace slag and hydrated lime. Depending on the ultimate end use for the concrete in building, slag cement may be used as substitute for Portland cement.
An object of the disclosed invention was to discover a partial substitute for the cementing agent, i.e., Portland cement or slag cement, which could be incorporated as an additive to the cement at a greatly reduced cost, to produce a concrete with as great or greater strength than known concretes and also be ecologically favorable to the environment.
These goals have been achieved through the discovery of the utilization of catalyst fines as an additive to the cementing agent in concrete mixtures. As used herein the terms "fines" or "catalyst fines" refers to fine particles produced from spent catalysts used in cracking gasoline. "Catalysts fines" is a term of art well known in the petroleum cracking industry field. For example, in the May 26, 1975 issue of the Oil and Gas Journal, page 96, the authors wrote as follows:
"Attention is now turning towards the effect of equipment design on the production of catalyst fines. Identifying where attrition takes place in a fluidcracking unit could lead to design changes which will reduce catalyst-fines production." PA1 Aerocat 2000: a semisynthetic fluid catalyst containing 35% Al.sub.2 O.sub.3. The ABD is 0.60, the surface area 300 m.sup.2 gm.sup.-1, and the pore volume 0.50 cm.sup.3 gm.sup.-1. PA1 Grade SS: a semisynthetic fluid catalyst containing 32% Al.sub.2 O.sub.3. It is supplied in two different pore volume grades: 0.58 cm.sup.3 gm.sup.-1 (ABD 0.51) and 0.70 cm.sup.3 gm.sup.-1 (ABD 0.47). The surface area of the latter is 280 m.sup.2 gm.sup.-1. PA1 Grade 58: 17.5% Al.sub.2 O.sub.3, fluid. The ABD is 0.65, the surface area 280-300 m.sup.2 gm.sup.-1, and the pore volume 0.36 cm.sup.3 gm.sup.-1. PA1 Grade 62: 17.5% Al.sub.2 O.sub.3 as 3/16.times.3/16 inch pellets. The ABD is 0.8, the surface area 280-300 m.sup.2 gm.sup.-1, and the pore volume 0.36 cm.sup.3 gm.sup.-1. PA1 Grade 63: 38% Al.sub.2 O.sub.3 as 3/16.times.3/16 inch pellets. The ABD is 0.8, the surface area 280-300 m.sup.2 gm.sup.-1, and the pore volume 0.27 cm.sup.3 gm.sup.-1. PA1 Grade 80: 38% Al.sub.2 O.sub.3, fluid. The ABD is 0.73, the surface area 125-135 m.sup.2 gm.sup.-1, and the pore volume 0.27 cm.sup.3 gm.sup.-1. PA1 Grade 100: 51% Al.sub.2 O.sub.3, microspheres. The ABD is 0.30, the surface area 105 m.sup.2 gm.sup.-1, and the pore volume 0.37 cm.sup.3 gm.sup.-1. PA1 Grade 110: pellets. PA1 Grade 110: Spherical pellets. PA1 Kao-Pellets: approximately 3/16.times.3/16 inch. PA1 Kao-Spheres: 45% Al.sub.2 O.sub.3, ca. 0.17 inch in diameter. The ABD is 0.77 and the surface area 90-100 m.sup.2 gm.sup.-1. PA1 Nalcat 783: a semisynthetic fluid catalyst, 33% Al.sub.2 O.sub.3. The ABD is 0.50, the surface area 280 m.sup.2 gm.sup.-1, and the pore volume 0.65-0.70 cm.sup.3 gm.sup.-1. PA1 Aerocat: 13% Al.sub.2 O.sub.3, fluid. The ABD is 0.49 and the pore volume 0.75 cm.sup.3 gm.sup.-1. PA1 Aerocat Triple A: 25% Al.sub.2 O.sub.3, fluid. The ABD is 0.43 and the pore volume 0.89 cm.sup.3 gm.sup.-1. PA1 Aerocat 3C-12: 3% MgO in low alumina, fluid. PA1 Aerocat eC-20: 3% MgO in high alumina, fluid. PA1 Low Alumina: 13% Al.sub.2 O.sub.3, fluid. The ABD is 0.43 and the pore volume 0.77 cm.sup.3 gm.sup.-1. PA1 High Alumina: 28% Al.sub.2 O.sub.3, fluid, in three different pore volumes: 0.70 cm.sup.3 gm.sup.-1 (ABD 0.46), 0.78 cm.sup.3 gm.sup.-1 (ABD 0.43), 0.88 cm.sup.3 gm.sup.-1 (ABD 0.39). PA1 SM-30: 27.5% MgO and 3% F, fluid. The ABD is 0.49 and the pore volume 0.72 cm.sup.3 gm.sup.-1. PA1 S-46: 13% Al.sub.2 O.sub.3, tablets. The ABD is 0.62, the surface area 280-315 m.sup.2 gm.sup.-1, and pore volume 0.61 cm.sup.3 gm.sup.-1. PA1 Durabead 1: 10% Al.sub.2 O.sub.3, spheres (beads). PA1 Nalcat Low Alumina: 13% Al.sub.2 O.sub.3, fluid. The ABD is 0.40, the surface area 520 m.sup.2 gm.sup.-1, and the pore volume 0.80-0.85 cm.sup.3 gm.sup.-1. PA1 Nalcat High Alumina: 25% Al.sub.2 O.sub.3, fluid. The ABD is 0.40-0.44, the surface area 440 m.sup.2 gm.sup.-1, and the pore volume 0.8-0.9 cm.sup.3 gm.sup.-1. PA1 Type FC-2: 13% Al.sub.2 O.sub.3, fluid. PA1 Type FC-3: 25% Al.sub.2 O.sub.3, fluid. PA1 Aerocat S-4: contains rare earth exchanged "Y" type molecular sieve in a semisynthetic matrix of 33% Al.sub.2 O.sub.3 content, fluid. The ABD is 0.53, the surface area 330 m.sup.2 gm.sup.-1, and the pore volume 0.57 cm.sup.3 gm.sup.-1. PA1 Aerocat TS-150: contains rare earth exchanged "Y" type molecular sieve in a matrix of synthetic silica-alumina (15% Al.sub.2 O.sub.3), fluid The ABD is 0.49, the surface are 600 m.sup.2 gm.sup.-1, and the pore volume 0.65 cm.sup.3 gm.sup.-1. PA1 Aerocat TS-170 and TS-260: contain rare earth exchanged "Y" type molecular sieve in a semisynthetic matrix with approximately 33% Al.sub.2 O.sub.3 content, fluid. The ABD is 0.55 and the pore volume 0.58 cm.sup.3 gm.sup.-1. PA1 XZ-15: 13% Al.sub.2 O.sub.3, fluid. The ABD is 0.40, the surface area 500 m.sup.2 gm.sup.-1, and the pore volume 0.88 cm.sup.3 gm.sup.-1. PA1 XZ-25: 36% Al.sub.2 O.sub.3, fluid. The ABD is 0.5, the surface area 340 m.sup.2 gm.sup.-1 and the pore volume 0.60 cm.sup.3 gm.sup.-1. PA1 XZ-36: 36% Al.sub.2 O.sub.3, fluid. The ABD is 0.55 and the pore volume 0.55 cm.sup.3 gm.sup.-1. PA1 XZ-40: fluid. PA1 Grade 800: microspheres, 48% Al.sub.2 O.sub.3. The ABD is 0.69, the surface area 210 m.sup.2 gm.sup.-1, and the pore volume 0.39 cm.sup.3 gm.sup.-1. PA1 Grade 810: pellets. PA1 HZ-1: pellets. PA1 Durabead 6B and Durabead 8: as spheres (beads); D-5 and D-7: fluid. PA1 KSF Series: "X" type molecular sieve in a matrix, fluid. PA1 KSG Series: "Y" type molecular sieve in a matrix, fluid.
Therefore, it is clear that catalyst fines are considered such as burdensome waste product in the petroleum industry that efforts are being made to reduce the attrition rate of catalysts in order to cut down on production of the catalyst fines.
With few exceptions, all commercial cracking catalysts are based upon silica-alumina combinations of one type or another. It is this alumina-silica combination in catalyst fines which allows them to be used as an additive to cements in making concrete. Therefore, catalyst fines which may be used in the disclosed invention must be produced from the aluminosilicate type cracking catalyst. Basically there are three classes of silica-alumina catalysts in the petroleum industry: (1) the acid-treated natural alumino-silicates; (2) the amorphous synthetic silica-alumina combinations; and (3) the crystalline, synthetic silica-alumina combinations.
Charles L. Thomas, in his book, Catalytic Processes and Proven Catalysts (1970 Academic Press) which is herein incorporated by reference, at pages 29-35, lists the commercially used alumino-silica catalysts. One of the sources of variance in these catalysts is the percentage of Al.sub.2 O.sub.3. In general, the composition of these catalysts consists of from about 13% Al.sub.2 O.sub.3 to up to about 51% Al.sub.2 O.sub.3 (with the balance being essentially silica). Other sources of variance are surface area, pore volume and the like characteristics. These types of subtleties which would be important in the petroleum industry for the maximum of efficiency of the catalyst are not of concern to the present invention. In short, any of the catalysts which would contain about 10% to about 51% alumina with the balance being silica would be acceptable to the present invention.
The disclosed invention represents a revolutionary concrete mixture which incorporates these heretofore useless and burdensome catalyst fines.